As a device for preventing products and the like placed on a mounting plate such as a shelf or rack from falling down due to the occurrence of an earthquake etc., for example, a device disclosed in JP 2010-273955 A (Patent Literature 1) (housing article fall prevention unit) has been proposed. In the housing article fall prevention unit disclosed in Patent Literature 1, a fall prevention arm is lowered from a standby state by driving an actuator that operates in response to a signal from a seismometer that detects vibrations due to earthquakes.
Therefore, according to the housing article fall prevention unit disclosed in Patent Literature 1, a housing article does not fall down by coming into contact with the fall prevention arm that has lowered due to the occurrence of an earthquake.